Method of forming collars for tearing strip containers



F. A. PRAHL METHOD OF FORMING COLLARS FOR TEARING STRIP CONTAINERS Filed April 5, 1932 nnentor 73 Si 1a 0551M MW 69%; I Ottornegs Patented Dec. 26, 1933 METHOD OF FORMING COLLARS FOR TEAR ING STRIP CONTAINERS Frederick A. Prahl, New York, N. Y., assignor to.

Continental Can Company, Inc., New York, N. Y., a corporation of New York Application April 5, 1932. Serial No. 603,391

, v 1 Claim.

The invention relates to new and useful improvements in a method of forming a collar which is to be inserted in a container having a tearing strip, and which remains a permanent I 5 part of the body of the container after the tearing strip has been removed and the container opened.

An object of the invention is to provide a method of forming a collar which enables the l0 collars to be made cheaply in the form of a band 0 a method of makingcollars for insertion in containers whereby the end portions of a plurality of collars may be simultaneously joined.

These and other objects will in part be 0bvious. and will in part be hereinafter more fully disclosed.

In the drawing which illustrates the steps in the method of making the collar and the completed container- 3 Figure 1 is a vertical sectional view through a container having a collar made by the improved method embodied therein;

Fig.2 is a view showing a metal blank rolled into a cylinder and the edge portion thereof joined preparatory to the cutting of the cylinder for forming circular ring blanks from which the collars are to be made;

Fig. 3 is a viewpartly diagrammaticand partly in section showing the cutting of the cylindrical blank into hollow sections;

lar sections;

Fig.5 is anenlarged sectional view through the The invention resides in a method of making collars to be inserted in containers having a tear- 55.jng strip. In Figure 1 of the drawing there is Fig, 4 is a plan view of one of said formed colshown one form of container having an inserted collar made by the improved method. The container as shown includes a body portion 1 which is preferably cylindrical, and which is provided with a bead 2. The body is also provided with a score line 3 and a score line 4, setting off a tearing strip 5 therebetween. The score line 4 is located a short distance above the bead 2. Located in the container is a collar 6 which is made by the improved method. The collar is65. made from a strip, the ends of which are joined as indicated at 7. The collar has the upper edge thereof rolled as indicated at 8 and is pro vided with an outwardly projecting bead '9. This outwardly projecting'bead 9 is so positioned and dimensioned as to make a line gripping and sealing contact with thewall of the container at a shortdistance below the score line 4, so that when the tearing strip is removed the grip between the bead and the 'bodyof the container is not disturbed. The collar is of smaller diameter than the inner wall of the container, thus producing 'a space'between the collar and the body wall. The lower portion of the collar makes gripping contact with the bead 2 in thebody wall and preferably terminates at or just below the crown of said bead. The can end indicated at 10 is provided with a depending .portion 11 bent back on itself to form a collar which is adapted to pass into the space betweenthe upper portion of the collar and the wall of the can body. The end 10 is secured to the body by a double seaml2. The container described above forms no part of my invention, but is shown and described in the application of Alfred L. Kronquest, Serial No. 593,915, filed February 18, 1932. The present invention has to do with the meth& 0d of forming collars for insertion'in containers of the type just described. In theforming of the collar a sheet of metal or a blank is rolled. into a cylinder indicated at 13, in Figure 2 of the drawing. As shown, the edge portion 14 overlaps the edge portion 15 and the adjacent faces, of the overlapping portions 'areunited by a solder bond. After the cylindrical blank has been com- '100 pleted it is then presented to a machine for cut- I ting said cylindrical blank into ring blanks from which the collars are to be formed. The cylindrical blank may be mounted. on a suitable mandrel and presented to cutting devices for cutting the cylinder simultaneously along the lines aa, bb, etc. Instead of cutting the cylinders along these lines simultaneously they may 7 be cut separately. The essential feature is that the cylinder, after the edge portions have been inner wall of the container.

united, shall be cut to form ring blanks wherein the ends of the strip thus formed have already been united. This accomplishes the joining of the ends of a plurality of collars simultaneously when the lap seam is formed, and this results in the making of a plurality of ring blanks at very little expense. It will be understood, of course, that instead of soldering the edge portions of the blank to form the cylinder, the edge portions may be united by spot welding or by folding of the metal parts, or in any other suitable way in order to secure permanent connection between the ends. The ring blank is indicated at 16 in Figures 3 and 4 of the drawing. It will be noted that the end portions 14 and 15, when lapped, are preferably shaped as shown in Fig. l, so that the outer face of the ring blank may be of uniform diameter throughout substantially its entire length. In other words, the end portion 15 is inwardly offset to permit the outer portion 14 of the lapping sections to lie in the circumference line of the ring blank.

In Fig. 3 of the drawing, there has been shown the improved method of cutting thecollar sections from the cylindrical blank whereby a plurality of collar sections are simultaneously formed. On the shaft 17 is a series of cutting disks 18 and on the shaft 19 is a series of cooperating cutting disks 20. The cutting disks 20 have their cutting edges 21 projecting from the peripheral surface of the disks and shaped so as to cooperate with the shaped recesses 22 in the inner cutting disk. Two things are accomplished by this shaping of the cutting disk. In the'first place, the edge of the collar is provided with an inwardly extending curved portion 23 which greatly aids in the die curling of the upper edge of the collar as indicated at 24 in Fig. 6. This die curling of the upper edge rounds up the collar and greatly strengthens the same by forming a hollow bead around the upper edge of the collar. The inwardly bent portion on the collar section or blank, as noted, greatly aids in the starting of the curl in the right direction. The bottom edge of the collar is formed with a burr which projects outwardly as indicated at 25 in Fig. 5 of the drawing. The upper edge of the collar section may be rolled into a bead, but it is preferable to die curl the bead in the manner just described. This produces what may be said to be a complete collar for insertion in a container. It is rounded up'so that it can be readily inserted in a cylindrical can body, and the lower burred edge of the collar will make firm gripping contact with the The collar may be held in the container in any suitable way. It is preferred, however, to form the collar of smaller diameter than the inner diameter of the container and to roll the bead 9 therein as indicated in Figures 1 and 7 of the drawing. This bead is made of sufi'lcient diameter so as to make a tight frictional grip with the inner wall of the container, and the bead is so proportioned that when the collar is fully seated in the can body,

the line of contact between the bead and the body wall is below the score line 4, while the line of contact between the burred edge 25 and the bead 2 of the can body is substantially at the crown of the bead 2. This not only aids in the firm gripping contact of the collar with the bead 2, but it produces a smooth edge 26 at the inner face of the collar. The beading of thecollar as described, further shapes the collar into a truly symmetrical circular form, and will retain the collar in this circular form during the handling thereof for the insertion of the collar in the container body. When the collar is provided with a bead which makes contact with the wall of the container for holding the collar in place, it may be readily inserted into a can body before the body is flanged and seated in the can body by the fianging die. The method of inserting the collar in the container body just referred to forms no part of the present invention, but is shown, described and claimed in the application of Alfred L. Kronquest, Serial No. 593,916, filed February As shown in Fig. 8, the blankis provided with a series of notches 27 in the edge thereof which are spaced so that when the blank is cut into collar portions and the collar finished, these notched edges will be at the upper end of the collar and in the lower lapped section. This greatly facilitates the curling of the edge to form the bead 8. r g

The invention has been described as having to do with the particular shapingof collar, but it will be understood that the collar may be of any shape, and may be attached to the container body in any way without departing from the spirit of the invention as set forth in the appended claim. The essential feature of the method consists in joining-the ends-of a series of collars simultaneously, and the subsequent cutting of the formed cylindrical blank into the collar sections While the cylindrical blank is shown as simultaneously cut into a plurality of collar sections, these collar sections-may be cut one at a time. It is also obvious that from certain aspects of the invention, the collar may be formed without any bead and other means used for providing a smooth upper edge than the curling of the collar.

Having thus described the invention, what I claim as new and desire to secure by LettersPatent, is:-- I

The method of making collars for insertion in tearing strip containers consisting in shaping a metal sheet so as to form a cylindrical blank and joining the edge portions thereof toform a cylinder which is of substantially uniform external diameter throughout, severing said cylindrical blank so as to'provide therefrom a series of ring blanks eachof which has one edge portion inwardly curved, subsequently rolling said inwardly curved portion of the ring blankto form a strengthening bead for the collar, and curving said ring blank intermediate the side edges thereof outwardly to provide a projecting portion of proper size and dimensions for frictionallycontacting with the inner wall of the container in which it is inserted.

FREDERICK A. PRAHL. 

